Transcoronary gradient of plasma microRNA 423-5p in heart failure: evidence of altered myocardial expression.

ABSTRACT

CONTEXT Elevated plasmatic microRNAs (miRs) are observed in heart failure (HF). However, the cardiac origin of these miRs remains unclear. OBJECTIVE: We calculated transcoronary gradients of miR-29b, miR-133a and miR-423-5p in 17 outpatients with stable systolic HF and in controls without structural cardiac disease. MATERIALS AND METHODS: MicroRNAs were measured by quantitative real-time polymerase chain reaction. RESULTS: Positive transcoronary miR gradients were observed in patients with HF but not in controls (p = 0.03). B-type natriuretic peptide (BNP) moderately correlated with the transcoronary gradients of miR-133a and miR-423-5p. DISCUSSION AND CONCLUSIONS: The difference in transcoronary gradients between HF outpatients and controls suggests that miR-423-5p has a cardiac origin. The positive correlation between miR-423-5p and BNP transcoronary gradients supports this hypothesis.